bug(parameter-in-retry): fix infinity recursion in retry input when parameter exists

lib/stepfunctions.js

@@ -148,6 +148,7 @@ class StepFunction extends EventEmitter {
     if (state.Parameters) {
       let newInput = {};
       const context = this.getContext();
+      input = context.Execution.Input;
       Object.keys(state.Parameters)
         .filter((parameter) => parameter !== 'comment')
         .map((parameter) => {
@@ -922,10 +923,11 @@ class StepFunction extends EventEmitter {
    */
   createContext(state, task, input, index = null, retries) {
     const id = +new Date();
+    this._lastInputBeforeRetry = retries ? this._lastInputBeforeRetry : input;
     this._current.context = {
       Execution: {
         Id: `arn:aws:states:ap-southeast-1:123456789012:execution:stateMachineName:${id}`,
-        Input: input,
+        Input: this._lastInputBeforeRetry,
         Name: +new Date(),
         RoleArn: 'arn:aws:iam::123456789012:role...',
         StartTime: new Date().toISOString(),
@@ -936,8 +938,7 @@ class StepFunction extends EventEmitter {
         RetryCount: retries || this._current.retries || 0,
       },
       StateMachine: {
-        Id:
-          'arn:aws:states:ap-southeast-1:123456789012:stateMachine:stateMachineName',
+        Id: 'arn:aws:states:ap-southeast-1:123456789012:stateMachine:stateMachineName',
         Name: this.Name,
       },
       Task: {

test/stepfunctions.test.js

@@ -725,6 +725,38 @@ describe('Stepfunctions', () => {
     );
   }, 8000);
 
+  it('can retry failing tasks and maintain the same transformed input', async () => {
+    const sm = new Sfn({
+      StateMachine: require('./steps/retry-transform-input.json'),
+    });
+    const args = { bar: 'baz' };
+    const firstFn = jest.fn((input) => {
+      const { retries, foo } = input;
+      expect(foo).toEqual(args);
+      if (retries === 3) {
+        return input;
+      }
+      class CustomError extends Error {
+        // empty
+      }
+      throw new CustomError('something happened');
+    });
+    const errorFn = jest.fn((input) => input);
+    const lastFn = jest.fn((input) => {
+      return input;
+    });
+    sm.bindTaskResource('First', firstFn);
+    sm.bindTaskResource('All', errorFn);
+    sm.bindTaskResource('Last', lastFn);
+    await sm.startExecution(args);
+    expect(firstFn).toHaveBeenCalled();
+    expect(errorFn).not.toHaveBeenCalled();
+    expect(lastFn).toHaveBeenCalled();
+    expect(sm.getExecutionResult()).toEqual(
+      expect.objectContaining({ retries: 3, foo: args }),
+    );
+  }, 8000);
+
   it('can retry failing tasks and finally catch', async () => {
     const sm = new Sfn({ StateMachine: require('./steps/retry.json') });
     const firstFn = jest.fn(() => {

test/steps/retry-transform-input.json

@@ -0,0 +1,39 @@
+{
+  "StartAt": "First",
+  "States": {
+    "First": {
+      "Type": "Task",
+      "Resource": "arn:aws:lambda:ap-southeast-1:123456789012:function:test",
+      "Parameters": {
+        "foo.$": "$",
+        "retries.$": "$$.State.RetryCount"
+      },
+      "Retry": [
+        {
+          "ErrorEquals": ["CustomError"],
+          "IntervalSeconds": 1,
+          "BackoffRate": 1,
+          "MaxAttempts": 3
+        }
+      ],
+      "Catch": [
+        {
+          "ErrorEquals": ["CustomError"],
+          "ResultPath": "$.error",
+          "Next": "All"
+        }
+      ],
+      "Next": "Last"
+    },
+    "All": {
+      "Type": "Task",
+      "Resource": "arn:aws:lambda:ap-southeast-1:123456789012:function:test",
+      "Next": "Last"
+    },
+    "Last": {
+      "Type": "Task",
+      "Resource": "arn:aws:lambda:ap-southeast-1:123456789012:function:test",
+      "End": true
+    }
+  }
+}